The Nerazzurri took the lead through Cristian Chivu, but a double from Riccardo Meggiorini turned the game on its head before Esteban Cambiasso earned his side a point.
The result is a hammer blow to Andrea Stramaccioni's side's hopes of challenging Juventus for the title, with the club now nine points adrift of the leaders and on a dismal run of four games without a win.
"Because of the way the game panned out, it's a point gained because in the second half, despite the difficulties, we always attacked and tried our best to win, but unfortunately we did not succeed," he told Sky Sport Italia.
"We need to look forward and continue working. We're in a difficult spell at the moment, but we will overcome it.
"When will it end? I don't know exactly, but we are trying to give our best like always. Sometimes we succeed, others we don't."
A leaky defence has been to blame for much of Inter's downfall, with seven goals conceded in their last four league games and, wary that the January transfer window is set to slam shut in just four day's time, Zanetti admits reinforcements would be a big boost.
"The president, coach, and the staff are always looking to improve the team. Anyone [who can improve the side] will be welcomed with open arms, but we must only think about ourselves for the moment and improving our performance."